## Scott A. Mitchell

### Publications:

• Papers 2007-
• Meshing papers 1994-2002.
• Computational Geometry triangulation papers and programs, including meshing. 1991-1994.

Anything I've ever published or written a report about at Sandia should be freely available to the public through our technical library, Sandia Publications, and also OSTI. Try entering "Mitchell, Scott" (with quotes) in the search filed at Sandia Publications. In addition to real publications and reports, you will find some miscellaneous half-backed drafts and sketches that morphed into something else or were dropped. (Thank you, freedom of information act!) If something valuable is missing let me know and I'll see about getting it added.

I am currently doing technical work related to mesh generation and improvement, surface reconstruction, with some sampling, uncertainty quantification and high dimensional space exploration, within the broader contexts of computational geometry, computer science, discrete math, and information theory. Some concluded projects include desiging a MANET protocol, researching validation process guidelines of computer models of how humans think, low-bandwidth authentication, and a military logistics siumlator called CoreSim. For a while I dabbled in computational topology, "forecasting" (uncertainty, statistics, and graph algorithms) over large-scale informatics graphs; and statistical techniques for finding the root-cause of faults in networked computer systems. Some information projects included data-streaming algorithms, e.g. approximate counting; and the geometry of distance functions for comparing probability distributions in information theory.

I've looked at sample based techniques, including their uses for mesh generation, integration, and uncertainty quantification. Often I consider uniform-random point samplngs with inter-sample inhibition distances and guaranteed domain coverage, and meshes from these point sets. These Poisson-disk samplings are popular in computer graphics, for integration-like problems such as texture synthesis, and in simulation for fracture mechanics, where non-randomness would spoil the outcome. We are working on using them, and line-search generalizations, for sampling for uncertainty quantification.

Let us use the following notation:
$n? = 1 + 2 + ... + n = n\left(n+1\right)/2$
n? = sum_{i=1:n} i = n(n+1)/2 [my idea]

tau = 2 pi [The Tau Manifesto by Michael Hartl].
Anyone who has messed with hypersphere volumes and areas should appreciate that.

I'm on the program committee for the 26th International Meshing Roundtable IMR, September 2017, the short-course chair and the papers co-chair. See you in Barcelona!
I taught the course "ALGORITHMIC GEOMETRY AND MESH GENERATION" at UNM in Fall 2010.
I organized a workshop on combinatorial algebraic topology in late August 2009; we wrote a summary report.
Here is a 2002 paper [bibtex] by Batagelj and Zaversnik about core decompositions of networks that lists me as a "liason" author linking two cores of Computational Geometry, which I recognize as Cubit mesh generation and theoretical mesh generation; see pages 7-8.
I have the dubious distinction of Jonathan Shewchuk using one of my papers from the 1990's as an example of standard practice that is "bad writing that's considered good." I thought the same thing as he did while I was writing it: "No value added, but it's expected." (I'm flattered he says the paper has high technical merit desipte that.) See "Conclusions that don't" in Three Sins of Authors in Computer Science and Math, and my paper Cardinality Bounds for Triangulations with Bounded Minimum Angle.
More advice I reread from time to time: abstract for experts vs. introduction for beginners and abstract in six easy sentences and Good Enough Practices in Scientific Computing and single-tasking and reviewing papers, an introduction.

### Scott's pages:

• Papers 2007+ and Google scholar profile and orcid
• CV March 2012
• Past manager web pages of Sandia's Optimization and Uncertainty Estimation department. Years 2002-2007.
• Meshing papers and Cubit-related pages. 1994-2002.
• Computational Geometry triangulation papers and programs, including meshing. 1991-1994.

• Some Quotes I like
• Personal interests

• ### Contact:

Scott A. Mitchell
Center for Computing Research
Sandia National Laboratories
P.O. Box 5800
MS 1320
Albuquerque, NM 87185-1320
Phone: (505) 845-7594
FAX: (505) 845-7442
E-mail: samitch@sandia.gov

1450 Innovation Pkwy SE
Albuquerque, NM 87123

Other Mitchells

### Biography:

I received a B.S in Applied Math, Engineering & Physics from the University of Wisconsin-Madison in 1988. I received an M.S. (1991) and Ph.D. (1993) in Applied Math from Cornell University. I worked the summer of 1991 at Xerox PARC with Marshall Bern and John Gilbert. Since Oct 1992 I've been at Sandia National Laboratories. I researched triangular and tetrahedral meshing algorithms via a computational geometry approach from 1992-1993. I was part of the Cubit project, doing mesh generation R&D from 1993-2000, and project leadership from 2000-2002. I did things like researching algorithms and existence proofs for hexahedral meshes and optimization for assigning the right number of edges locally so the model can be meshed globally. I managed the Optimization and Uncertainty Estimation department from 2002-2007. I served in various capacities on various programs, including LDRD (internal research program) and NNSA's ASC program. I decided I missed building things and figuring things out for myself and moved on to technical work in 2007. After some informatics projects, I gravitated back to geometry and mesh generation in about 2011, with some connections to computer graphics and uncertainty.

### Partners, visitors, summer students, etc. not exhaustive

• My short Sandia page
• CSRI Wiki Sandia only.
• Computer Science Research Institute facility
• Sandia Long-term visitor housing and social sites
• Scott's Computational Geometry triangulation papers and programs.
• Scott's Meshing and Cubit-related pages.
• Disk-sampling optimization, meshing, and other papers 2007+
• My center at Sandia, Center for Computing Research, CCR
• RGMIA: Research Group in Mathematical Inequalities and Applications
• A history of measurements is interesting and mentions the cubit
• Dakota optimization and uncertainty analysis framework
• Cubit mesh generation tool suite
• MESQUITE Mesh Quality Improvement Toolkit web
• MESQUITE Mesh Quality Improvement Toolkit web pointer
• Sandia ASC (formerly ASCI)
• U.S. DOE Office of Science, Advanced Scientific Computing Research (ASCR)
• International Meshing Roundtable
• Computational Geometry Bibliography is a good place to look up papers.
• Sandia Anywhere.
• Sandia's SRN <internal only>.